Her second EP, The Apple Tree, was released in April 2012 via AWAL and reached No. 6 on the iTunes download charts after receiving airplay on BBC Radio 1, and also reached No. 1 on the iTunes singer/songwriter chart. On 9 October 2012, Nesbitt embarked on her second UK headline tour, to support the release of her debut single, “Boy”, under new label, Island Records. The tour included support from singer-songwriter Josh Kumra and singer-songwriter Billy Lockett. The tour commenced on 9 October 2012 at Oran Mor, Glasgow, Scotland and finished on 18 October 2012 at Dingwalls, London, England. Her third EP, Stay Out, was released on 8 April 2013; its title track of the same name entered the charts at No. 21 in April 2013. Her next EP, Way in the World, was released on 21 July 2013. The title track was released as a single, and the music video released on 12 June 2013. Nesbitt’s next single was a cover of the Fleetwood Mac song, “Don’t Stop”, and is used in an advert for the department store John Lewis. On 6 September 2013, Nesbitt sang “Flower of Scotland” at Hampden Park before Scotland faced Belgium in a Group A World Cup Qualifier.

On 25 November 2013, Nesbitt announced on her Twitter and Facebook pages that her debut album, Peroxide, would be released on 17 February 2014 in the United Kingdom. Nesbitt did an album signing tour around the UK, starting in Edinburgh, on the day her album was released. Peroxide entered the UK Album Charts at number 1 in Scotland and 11 in the rest of the UK.| Scottish Albums (OCC) |align=”center”|1; | UK Albums (OCC) |align=”center”|11 The lead single from the album, “Selfies” was released on 9 February 2014. She released her fifth EP, Nina Nesbitt, exclusively in the US on 1 April 2014.

In 2016, Nesbitt announced the release of her newest EP, Modern Love, featuring her “radical new look.” She also announced a three-date UK Tour, that took place from 26 to 28 January. Following its World Exclusive on Radio 1, her single “Chewing Gum” became available for download on Apple Music and Spotify on 10 January. On 27 April, Nesbitt performed at the Young Scot Awards at Edinburgh’s International Conference Centre. In June, she started the project Songs I Wrote For You, where she asked her fans to send her their personal love stories and she would write a song about it. In October 2016, she released a five-track EP titled Life in Colour with the songs of the project under her own label.

In May 2016, Nesbitt disclosed that she had left her record label and was now an independent artist. In November 2016, Nesbitt signed a record deal with indie label Cooking Vinyl. On 2 July 2017, she served as a supporting act for Justin Bieber during British Summer Time in Hyde Park, London. She released a new single, “The Moments I’m Missing”, on 14 July 2017. On 8 September 2017 she released her next single, “The Best You Had”, which was made Greg James’ ‘Tune Of The Week’ on Radio 1 and added to the Radio 1 playlist. Taylor Swift later added “The Best You Had” to her ‘Favourite Songs’ playlist on Apple Music and Spotify, while actress Chloë Grace Moretz tweeted about the song to her followers. Nesbitt then released “Somebody Special” as the third single from her second album.

In 2016, Nesbitt revealed she was having trouble with people stalking her.

In October 2017, she played two intimate shows in New York City and Los Angeles. In December 2017, Nesbitt won the ‘Evolution Award’ at the SSE Scottish Music Awards.

In summer 2018, Nesbitt played twelve festivals in the UK, and also performed at SXSW, MIDEM and The Great Escape. She later sold out three consecutive London shows (at Heaven, The Islington and Camden Assembly), and supported acts such as James Arthur, Jesse McCartney, MAX and Lewis Capaldi on tours.

On 10 August 2018, Nesbitt released her fourth single from the album, “Loyal to Me”, which was produced by Fraser T Smith. In October 2018, Nesbitt announced that her second album, The Sun Will Come Up, the Seasons Will Change will be released on 1 February 2019 through Cooking Vinyl.

The Sun Will Come Up, The Seasons Will Change was released on 1 February 2019, to a positive critic reaction. The Independent awarded the record four stars and The Times gave it three, whilst CelebMix awarded the album five stars saying, “February is far too early to talk about albums of the year. But, really, is it going to get better than this?” . On the same day, Nesbitt also released a new music video for her fifth single from the album, titled “Is It Really Me You’re Missing?”. Nesbitt then embarked on a headlining Tour to support The Sun Will Come Up, the Seasons Will Change, with the North American and UK legs spanning from February to April. She also toured in Australia and New Zealand from 28 May to 1 June.

In March 2019, it was announced that Nesbitt would be supporting Jess Glynne on the American leg of the Always In Between Tour.